Jet Research Center Drill Collar Severing Tool P/N 101293224 Rev. K
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Jet Research Center, 8432 South I-35W, Alvarado, Texas, 76009-9775, USA
Telephone 1-817-761-2000; Toll Free 1-800-451-5403; Fax 1-817-783-5812; Website www.jetresearch.com
5.8 Remove the firing head and extension mandrel from the tool string. Install the shunt
plug (16) into the top of the firing head.
5.9 Attach the detonator assembly (13) to the end of the extension mandrel by pushing
the boot of the detonator assembly onto the end of the extension mandrel. Wrap the
ground wire clockwise, looking from the lower end, into the o-ring groove above the
boot. Push the o-ring (the o-ring size 020 is included with the detonator assembly) up
into the groove ensuring that the end and approximately 2 inches (50 mm) of ground
wire is pressed between the o-ring and the mandrel. (Note if using RED, that no
ground wire is present as ground is made from barrel spring on body of detonator to
the adapter when installed).
5.10 Remove the tape and/or label and the temporary shunt wire from the detonator
assembly.
5.11 If running RED, Install the appropriate adapter (11) for the detonator assembly being
used. Refer to Table 3 for appropriate parts.
5.12 Make up the protective holder (17), hand tight, to the adapter, extension mandrel and
detonator assembly. Wrench tighten the firing head, extension mandrel and adapter.
The shunt plug and protective holder remain hand tight.
5.13 Remove the shunt plug.
5.14 Check the firing head, extension mandrel, detonator assembly and adapter for
electrical continuity between the top contact and the body of the firing head using a
blasters multimeter in the 200 ohm position. The meter should read the resistance of
the detonator assembly, typically between 49 and 61 Ohms for the resistorized
detonator. Follow specific procedures for measuring continuity with RED.
5.15 With the protective holder still in position, make up the firing head, extension
mandrel, detonator, adapter and protective holder assembly to the tool string wrench
tight. The detonator is now connected to the firing circuit. The firing circuit must
remain in ‘SHORT’ and ‘SAFE’ position.
5.16 Remove the protective holder from the adapter, extension mandrel and detonator
assembly.
5.17 Make up the DCST explosive assembly to the adapter, extension mandrel and
detonator assembly and tighten with a strap wrench.